Ultrahigh-silicon low-aluminum iron tailing-based high-strength lightweight ceramsite and segmented temperature control preparation method thereof

Abstract

The application belongs to the technical field of tailing resource processing, and particularly discloses a kind of ultra-high silicon low aluminum iron tailing mud-based high-strength lightweight ceramsite and a segmented temperature control preparation method thereof.The application first mixes ultra-high silicon low aluminum iron tailing mud, composite fluxing agent (potash feldspar and heavy calcium carbonate), aluminosilicate reinforcing agent and pore former to obtain green balls; then after the green balls are air dried, they are subjected to segmented temperature control sintering to obtain ultra-high silicon low aluminum iron tailing mud-based high-strength lightweight ceramsite; the chemical composition of the ultra-high silicon low aluminum iron tailing mud is: SiO2≥80%, Al2O3≤1%, Fe2O3=10-20%.The application effectively solves the problems of low solid waste content, high sintering temperature, large product performance fluctuation (excessive water absorption, insufficient strength, etc.) and insufficient research on high-iron tailings in the existing treatment scheme.

Description

Technical Field

[0001] This invention relates to the field of tailings resource utilization technology, and in particular to a high-strength lightweight ceramsite based on ultra-high silicon, low aluminum, and iron tailings and its segmented temperature-controlled preparation method. Background Technology

[0002] Iron tailings are the largest and most abundant type of metal tailings, and a key and challenging aspect of the comprehensive utilization of bulk industrial solid waste. With an average iron ore grade of only 32.67%, the production of 1 ton of iron concentrate generates an average of 2.5 tons of iron tailings, resulting in an annual discharge exceeding 550 million tons. However, the highest comprehensive utilization rate is only 33%. The long-term accumulation of large quantities of iron tailings not only occupies land resources but also poses environmental safety hazards such as dam failure and heavy metal pollution.

[0003] Expanded clay aggregate (ECA) is one of the most promising directions for the large-scale utilization of iron tailings, possessing excellent properties such as lightweight, high strength, and thermal insulation, and is widely used in construction, ecological restoration, and other fields. High-silica iron tailings are the most widely distributed, but their high SiO2 content and low Al2O3 content result in extremely poor sintering activity, posing a technical challenge in EC preparation. According to the Riley phase diagram, the optimal EC formation range requires approximately 55-70% SiO2, 12-20% Al2O3, and 10-20% fluxing components. However, the composition of a certain ultra-high silica, low-alumina iron tailings sludge is as follows: 83.45% SiO2, 0.47% Al2O3, and 14.3% Fe2O3. It is evident that the SiO2 content of this ultra-high silica, low-alumina iron tailings sludge far exceeds the optimal range, and the Al2O3 content is severely insufficient, classifying it as a difficult-to-sinter solid waste recognized in the industry.

[0004] The existing processing methods have the following main drawbacks: (1) Low solid waste content: For ultra-high silicon and low aluminum iron tailings, the existing technology generally has a solid waste content of less than 50%, and natural silicon and aluminum minerals such as clay and shale are required as the main skeleton raw materials. This not only consumes a large amount of non-renewable mineral resources, but also makes it difficult to achieve large-scale disposal of tailings.

[0005] (2) High sintering temperature: The sintering temperature of existing high-silica tailings ceramsite is mostly 1280~1320℃, which is 50~100℃ higher than that of traditional clay ceramsite, resulting in high energy consumption and cost.

[0006] (3) Large fluctuations in product performance: Under high solid waste content, ceramsite is prone to problems such as excessive water absorption (>15%) and insufficient strength (<5MPa), making it difficult to consistently meet national standards.

[0007] (4) Insufficient research on medium iron tailings: Existing research on the application of ultra-high silica tailings is mostly focused on low iron (Fe2O3<10%) ultra-high silica tailings, which require the addition of iron-based flux; however, there has been no systematic research on how to utilize the natural iron of medium iron (Fe2O3=10~20%) ultra-high silica tailings to achieve relatively low-temperature sintering, while avoiding the problem of easy deformation and adhesion of high iron tailings.

[0008] Therefore, how to provide a high-strength, lightweight ceramsite based on ultra-high silica, low aluminum, and iron tailings and its segmented temperature-controlled preparation method to achieve the treatment of ultra-high silica, low aluminum, and iron tailings is an urgent problem to be solved in this field. Summary of the Invention

[0009] In view of this, the present invention provides a high-strength lightweight ceramsite based on ultra-high silica, low aluminum, and iron tailings and its segmented temperature-controlled preparation method, in order to solve the problems of existing methods that make it difficult to utilize ultra-high silica, low aluminum, and iron tailings for resource recovery, have low utilization rates and poor final product performance, as well as the problem of high processing temperatures causing energy waste.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: A segmented temperature-controlled preparation method for ultra-high silica, low aluminum, and iron tailings-based high-strength lightweight ceramsite includes the following steps: 1) Mix ultra-high silica, low aluminum, iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent to form pellets, thus obtaining raw material pellets; 2) The raw material pellets are air-dried and then sintered in stages at controlled temperature to obtain ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite. The chemical composition of the ultra-high silicon, low aluminum, and iron tailings is: SiO2 ≥ 80%, Al2O3 ≤ 1%, Fe2O3 = 10~20%; The composite flux includes potassium feldspar and heavy calcium carbonate.

[0011] Preferably, the mass ratio of the ultra-high silica, low aluminum, iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent is 60~61:20~30:10~18:0.5~2.5.

[0012] Preferably, during the mixed pelletizing process, the mass percentage of ultra-high silica and low aluminum iron tailings is ≥60%.

[0013] Preferably, the mass ratio of potassium feldspar to heavy calcium carbonate in the composite flux is 1.5~2.5:1; The potassium feldspar is ≥80 mesh; The heavy calcium carbonate is ≥100 mesh.

[0014] Preferably, the aluminosilicate reinforcing agent includes kaolin and sodium bentonite; The mass ratio of kaolin to sodium bentonite is 1.5~2.5:1; The kaolin clay is ≥100 mesh; The sodium-based bentonite is ≥80 mesh.

[0015] Preferably, the pore-forming agent comprises anthracite powder; The pore-forming agent has a mesh size of ≥100.

[0016] Preferably, the particle size of the raw material balls is 5~20mm.

[0017] Preferably, the segmented temperature-controlled sintering includes four stages of sequential temperature increases; The final temperature of the first stage is 500℃, the final temperature of the second stage is 600℃, the final temperature of the third stage is 1250℃, and the sintering temperature of the fourth stage is equal to the final temperature of the third stage. The heating rate in the first stage is 5~10℃ / min, the heating rate in the second stage is 2~4℃ / min, the heating rate in the third stage is 4~8℃ / min, and the holding time in the fourth stage is 25~50min.

[0018] Another objective of this invention is to provide a high-strength, lightweight ceramsite based on ultra-high silica, low aluminum, and iron tailings prepared by the above-mentioned method, wherein the ultra-high silica, low aluminum, and iron tailings-based high-strength, lightweight ceramsite has a 1-hour water absorption rate ≤10%, a cylinder compressive strength ≥7 MPa, and a bulk density of 800~1200 kg / m³. 3 .

[0019] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: This invention uses ultra-high silica and low aluminum iron tailings as the main raw material. Through dual regulation of a composite flux (potassium feldspar + heavy calcium carbonate) and an aluminosilicate reinforcing agent, the chemical composition of the raw material system is adjusted to a reasonable range for ceramic formation. Simultaneously, it fully utilizes the 10-20% natural Fe2O3 in the iron tailings to form a triple synergistic fluxing effect with the composite flux. Combined with a segmented temperature-controlled sintering process, efficient sintering is achieved at 1250℃ to prepare high-strength, lightweight ceramic particles. Compared with existing methods, this invention has the following advantages: 1. Environmental benefits High-value utilization of solid waste: Achieve high-content utilization of ultra-high silicon, low aluminum, and iron tailings (up to 60% or more), significantly reducing land occupation and environmental risks caused by tailings stockpiling.

[0020] Conserve natural resources: reduce the exploitation of natural mineral resources and protect the ecological environment.

[0021] 2. Economic benefits

[0022] The cost of main materials is almost zero: using ultra-high silicon, low aluminum, and low iron tailings (industrial solid waste) instead of natural clay as the main raw material, the procurement cost of main materials is significantly lower than that of traditional clay ceramsite.

[0023] Outstanding energy-saving and consumption-reducing effects: The sintering temperature is controlled at 1250℃, which is 50-70℃ lower than the traditional process (1280~1320℃) for similar ultra-high silica tailings, significantly reducing production energy consumption and carbon emissions.

[0024] Significant overall cost advantages: Free main materials + low-temperature sintering result in lower overall production costs than traditional processes, making the product highly competitive in the market.

[0025] High added value: Product performance far exceeds the national standard 1000 level requirements, and can be applied to high-end markets such as high-strength concrete and prefabricated buildings, with higher selling price and profit margin.

[0026] 3. Technical Effects

[0027] The product exhibits excellent performance: the obtained high-strength lightweight ceramsite has a 1-hour water absorption rate ≤10%, a cylinder compressive strength ≥7.0MPa, and a bulk density of 800~1200kg / m³. 3 It meets the requirements for 1000-grade high-strength lightweight aggregates in GB / T 17431.1-2010.

[0028] Stable and controllable process: It adopts conventional mixing, pelletizing and sintering equipment, without the need to modify the existing production line, and is easy to promote industrially.

[0029] High yield: The segmented temperature-controlled sintering process effectively avoids the cracking problem of green balls with high quartz content, and the product qualification rate is ≥90%. Detailed Implementation

[0030] This invention provides a segmented temperature-controlled preparation method for ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite, comprising the following steps: 1) Mix ultra-high silica, low aluminum, iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent to form pellets, thus obtaining raw material pellets; 2) The raw material pellets are air-dried and then sintered in stages at controlled temperature to obtain ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite.

[0031] In this invention, the mass ratio of the ultra-high silicon, low aluminum, and iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent is 60~61:20~30:10~18:0.5~2.5. Under the above ratio, the specific addition amount of ultra-high silicon, low aluminum, and iron tailings can be 60.2, 60.4, 60.5, 60.6, or 60.8; the specific addition amount of composite flux can be 22, 24, 25, 26, or 28; the specific addition amount of aluminosilicate reinforcing agent can be 11, 12, 13, 14, 15, 16, or 17; and the specific addition amount of pore-forming agent can be 0.6, 0.8, 1, 1.2, 1.5, 1.8, 2, or 2.2.

[0032] In this invention, during the mixed pelletizing process, the mass percentage of ultra-high silica and low aluminum iron tailings is ≥60%, specifically 60.2%, 60.4%, 60.5%, 60.6%, 60.8%, or 61%.

[0033] In this invention, the chemical composition of the ultra-high silica, low aluminum, and iron tailings is as follows: SiO2 ≥ 80%, specifically 81%, 82%, 83%, 83.45%, 84%, and 85%; Al2O3 ≤ 1%, specifically 0.2%, 0.4%, 0.47%, 0.5%, 0.6%, and 0.8%; Fe2O3 = 10~20%, specifically 12%, 14%, 14.3%, 15%, 16%, and 18%.

[0034] In this invention, the ultra-high silica and low aluminum iron tailings ≥80 mesh means that its particle size is less than or equal to a sieve with a mesh size of 80 mesh, the same below.

[0035] In this invention, the composite flux comprises potassium feldspar and heavy calcium carbonate.

[0036] In this invention, the mass ratio of potassium feldspar to heavy calcium carbonate in the composite flux is 1.5~2.5:1, preferably 1.8~2.2:1, and more preferably 2:1.

[0037] In this invention, the potassium feldspar is ≥80 mesh, and the potassium feldspar contains K2O ≥7%, specifically 8%, 9%, or 10%.

[0038] In this invention, the heavy calcium carbonate is ≥100 mesh, and the calcium carbonate content in the heavy calcium carbonate is preferably ≥95%, specifically 96%, 97%, 98%, or 99%.

[0039] In this invention, the aluminosilicate reinforcing agent comprises kaolin and sodium bentonite, wherein the mass ratio of kaolin to sodium bentonite is 1.5~2.5:1, preferably 1.8~2.2:1, and more preferably 2:1.

[0040] In this invention, the kaolin is ≥100 mesh, and the Al2O3 content in the kaolin is preferably ≥48%, specifically 49%, 50%, 51%, or 52%.

[0041] In this invention, the sodium-based bentonite is ≥80 mesh and the swelling capacity of the sodium-based bentonite is ≥10 mL / g, specifically 11 mL / g, 12 mL / g, 13 mL / g, 14 mL / g, or 15 mL / g.

[0042] In this invention, the pore-forming agent includes anthracite powder with a fixed carbon content of ≥80%, specifically 81%, 82%, 83%, 84%, or 85%.

[0043] In this invention, the pore-forming agent has a mesh size of ≥100 mesh.

[0044] In this invention, the particle size of the raw material balls is 5~20mm, specifically 6mm, 8mm, 10mm, 12mm, 14mm, 15mm, 16mm, or 18mm.

[0045] In this invention, the air-drying time is 10-15 hours, specifically 11 hours, 12 hours, 13 hours, or 14 hours.

[0046] In this invention, the segmented temperature-controlled sintering includes four stages of sequential heating; The final temperature of the first stage is 500℃, the final temperature of the second stage is 600℃, the final temperature of the third stage is 1250℃, and the sintering temperature of the fourth stage is equal to the final temperature of the third stage. The heating rate in the first stage is 5~10℃ / min, specifically 6℃ / min, 7℃ / min, 8℃ / min, and 9℃ / min; the heating rate in the second stage is 2~4℃ / min, specifically 2.2℃ / min, 2.5℃ / min, 2.8℃ / min, 3℃ / min, 3.2℃ / min, 3.5℃ / min, and 3.8℃ / min; the heating rate in the third stage is 4~8℃ / min, specifically 4.5℃ / min, 5℃ / min, 5.5℃ / min, 6℃ / min, 6.5℃ / min, 7℃ / min, and 7.5℃ / min; and the holding time in the fourth stage is 25~50min, specifically 30min, 35min, 40min, and 45min.

[0047] In this invention, the segmented temperature-controlled sintering specifically involves heating to the final temperature of the first stage at a heating rate of the first stage, then heating to the final temperature of the second stage at a heating rate of the second stage, then heating to the final temperature of the third stage at a heating rate of the third stage, and finally holding at the final temperature of the third stage for a period of time to complete the segmented temperature-controlled sintering.

[0048] In this invention, the first stage achieves rapid dehydration to remove free water; the second stage involves slow passage through the quartz phase transformation zone (573°C) to avoid cracking; the third stage involves rapid heating to prevent the flux from prematurely forming a liquid phase; and the fourth stage involves heat preservation and sintering to form a dense matrix.

[0049] This invention also provides a high-strength, lightweight ceramsite based on ultra-high silica, low aluminum, and iron tailings prepared by the above method. The ultra-high silica, low aluminum, and iron tailings-based high-strength, lightweight ceramsite has a 1-hour water absorption rate ≤10%, a cylinder compressive strength ≥7 MPa, and a bulk density of 800~1200 kg / m³. 3 .

[0050] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Example 1

[0052] Test materials: Ultra-high silica and low aluminum iron tailings: SiO2 83.45%, Al2O3 0.47%, Fe2O3 14.3%; Pretreatment standard: dry at 105℃ for 2 hours, pass through an 80-mesh sieve, and collect the sieve fraction (take the smallest particle size component). Potassium feldspar: K2O≥8%; The industrial-grade potassium feldspar used in this example contains 8.1% K2O, 74.18% SiO2, and 13.13% Al2O3; Pretreatment standard: Dry at 105℃ for 2 hours, pass through an 80-mesh sieve, and collect the sieve results; Kaolin: Al2O3≥48%; The kaolin used in this example has an Al2O3 content of 48.12%, SiO2 of 47.8%, and Fe2O3 of 0.19%; Pretreatment standard: Dry at 105℃ for 2 hours, pass through a 100-mesh sieve, and collect the sieve results; Heavy calcium carbonate: CaCO3≥95%; The heavy calcium carbonate used in this example contains 95.01% CaCO3, 1.01% SiO2, and 0.08% Al2O3; Pretreatment standard: Dry at 105℃ for 2 hours, pass through a 100-mesh sieve, and collect the sieve results; Sodium-based bentonite: expansion capacity ≥10mL / g; the sodium-based bentonite used in this example contains 60.21% SiO2, 18.04% Al2O3, and 2.94% K2O; pretreatment standard: dry at 105℃ for 2 hours, pass through an 80-mesh sieve, and sieve the sample; Anthracite powder: fixed carbon ≥ 80%; the anthracite powder used in this embodiment has 80% fixed carbon and 12% volatile matter; pretreatment standard: dry at 105℃ for 2 hours, pass through a 100-mesh sieve, and take the sieve results.

[0053] Preparation method: Weigh out the raw materials according to the formula (61% ultra-high silicon low aluminum iron tailings, 17% potassium feldspar, 8% heavy calcium carbonate, 8% kaolin, 5% bentonite, 1% anthracite powder, by mass percentage), mix the dry powders for 15 min; then add 18% water by mass to form pellets with a particle size of 5-20 mm; air dry at room temperature for 12 h; then sinter according to a segmented temperature control regime: room temperature → 500℃ (heating rate 8℃ / min), 500 → 600℃ (heating rate 3℃ / min), 600 → 1250℃ (heating rate 6℃ / min), hold at 1250℃ for 30 min; cool with the furnace to obtain ultra-high silicon low aluminum iron tailings-based high-strength lightweight ceramsite.

[0054] The bulk density, cylinder compressive strength and 1-hour water absorption rate of the above-mentioned high-strength lightweight ceramsite were tested. The test methods are as described in GB / T17431.2-2010 "Lightweight aggregates and their test methods - Part 2: Lightweight aggregates test methods".

[0055] Performance: 6.1% water absorption rate in 1 hour, bulk density 1000 kg / m³ 3 The cylinder compressive strength is 9.72 MPa.

[0056] The ceramsite prepared in this embodiment meets the requirements of GB / T 17431.1-2010 for medium density grade 1000 high-strength lightweight aggregate (1h water absorption ≤10%, bulk density ≤1200kg / m³). 3 The cylinder compressive strength is ≥1.5MPa, and the cylinder compressive strength far exceeds the national standard requirements.

[0057] Example 2 (1.5% anthracite powder)

[0058] Formula: 60.5% iron tailings, 17% potassium feldspar, 8% heavy calcium carbonate, 8% kaolin, 5% bentonite, and 1.5% anthracite powder. Sintering process is the same as in Example 1.

[0059] Performance: 9% water absorption rate in 1 hour, bulk density 946 kg / m³ 3 The cylinder compressive strength is 6.5 MPa.

[0060] The ceramsite prepared in this embodiment meets the requirements of GB / T 17431.1-2010 for high-strength lightweight aggregates with a density grade of 1000, and its compressive strength far exceeds the national standard requirements.

[0061] Example 3 (2% anthracite powder)

[0062] Formula: 60% iron tailings, 17% potassium feldspar, 8% heavy calcium carbonate, 8% kaolin, 5% bentonite, and 2% anthracite powder. Sintering process is the same as in Example 1.

[0063] Performance: 10% water absorption rate in 1 hour, bulk density 904 kg / m³ 3The cylinder compressive strength is 6.14 MPa.

[0064] The ceramsite prepared in this embodiment meets the requirements of GB / T 17431.1-2010 for high-strength lightweight aggregates with a density grade of 1000, and its compressive strength far exceeds the national standard requirements.

[0065] Comparative Example 1 (sintering temperature 1180℃)

[0066] The formula is the same as in Example 1, but the sintering process is changed to: maximum temperature 1180℃, holding time 30min, and the rest remain unchanged.

[0067] Results: No effective continuous glass phase was formed, the green pellets were not completely sintered, and the inside was powdery.

[0068] Comparative Example 2 (sintering temperature 1240℃)

[0069] Formula: 60% iron tailings, 15% potassium feldspar, 8% heavy calcium carbonate, 9% kaolin, 5% bentonite, and 3% anthracite powder. The sintering process was changed to: maximum temperature 1240℃, holding time 30 min, and the rest remained the same as in Example 1.

[0070] Performance: 8.2% water absorption rate in 1 hour, bulk density 1307 kg / m³ 3 The cylinder compressive strength is 1.78 MPa.

[0071] Bulk density 1307 kg / m³ 3 This does not meet the requirement of a bulk density ≤1200kg / m³ as specified in GB / T 17431.1-2010. 3 Requirements.

[0072] Comparative Example 3 (3% anthracite powder)

[0073] Formula: 60% ultra-high silica, low aluminum, and iron tailings, 15% potassium feldspar, 8% heavy calcium carbonate, 9% kaolin, 5% bentonite, and 3% anthracite powder. Sintering process is the same as in Example 1.

[0074] Performance: 18% water absorption rate in 1 hour, bulk density 840 kg / m³ 3 The cylinder compressive strength is 6.54 MPa.

[0075] The comparative example showed a water absorption rate of 18% in 1 hour, which does not meet the requirement of ≤10% water absorption rate in GB / T 17431.1-2010.

[0076] Comparative Example 4

[0077] Formula: 60% iron tailings, 15% potassium feldspar, 8.6% heavy calcium carbonate, 7.5% kaolin, 6.7% bentonite, and 2.2% anthracite powder. Sintering process is the same as in Example 1.

[0078] Performance: 11% water absorption rate in 1 hour, bulk density 1103 kg / m³ 3 The cylinder compressive strength is 1.34 MPa.

[0079] The comparative example showed a water absorption rate of 11% in 1 hour, which does not meet the requirement of ≤10% water absorption rate in GB / T 17431.1-2010.

[0080] By comparing Examples 1-3 of the present invention with Comparative Examples 1-4, the following conclusions can be drawn: Formula effectiveness: The low Al2O3 framework and high flux ratio formula system designed in this invention can effectively solve the sintering problem of ultra-high silicon and low aluminum iron tailings and achieve a high solid waste content of more than 60%.

[0081] Precise sintering temperature window: Comparison of Examples 1-3 (1250℃) with Comparative Example 1 (1180℃) and Comparative Example 2 (1240℃) proves that 1250℃ is the optimal temperature for effective sintering of this system, while 1180℃ and 1240℃ cannot achieve effective sintering.

[0082] Product performance meets standards: The 1-hour water absorption rate, bulk density, and compressive strength of the products in Examples 1-3 fully meet the requirements of GB / T17431.1-2010 for high-strength lightweight aggregates of density grade 1000, and the compressive strength far exceeds that of similar products sold in the market.

[0083] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0084] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A segmented temperature-controlled preparation method for ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite, characterized in that, Includes the following steps: 1) Mix ultra-high silica, low aluminum, iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent to form pellets, thus obtaining raw material pellets; 2) The raw material pellets are air-dried and then sintered in stages at controlled temperature to obtain ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite. The chemical composition of the ultra-high silicon, low aluminum, and iron tailings is: SiO2 ≥ 80%, Al2O3 ≤ 1%, Fe2O3 = 10~20%; The composite flux includes potassium feldspar and heavy calcium carbonate.

2. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 1, characterized in that, The mass ratio of the ultra-high silica, low aluminum, iron tailings, composite flux, aluminosilicate reinforcing agent, and pore-forming agent is 60~61:20~30:10~18:0.5~2.

5.

3. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 2, characterized in that, During the mixed pelletizing process, the mass percentage of ultra-high silica and low aluminum iron tailings is ≥60%.

4. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to any one of claims 1 to 3, characterized in that, The mass ratio of potassium feldspar to heavy calcium carbonate in the composite flux is 1.5~2.5:1; The potassium feldspar is ≥80 mesh; The heavy calcium carbonate is ≥100 mesh.

5. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 4, characterized in that, The aluminosilicate reinforcing agent includes kaolin and sodium bentonite; The mass ratio of kaolin to sodium bentonite is 1.5~2.5:1; The kaolin clay is ≥100 mesh; The sodium-based bentonite is ≥80 mesh.

6. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 5, characterized in that, The pore-forming agent includes anthracite powder; The pore-forming agent has a mesh size of ≥100.

7. A segmented temperature-controlled preparation method for ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 5 or 6, characterized in that, The raw material balls have a particle size of 5~20mm.

8. The segmented temperature-controlled preparation method of ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite according to claim 7, characterized in that, The segmented temperature-controlled sintering includes four stages of sequential temperature increases; The final temperature of the first stage is 500℃, the final temperature of the second stage is 600℃, the final temperature of the third stage is 1250℃, and the sintering temperature of the fourth stage is equal to the final temperature of the third stage. The heating rate in the first stage is 5~10℃ / min, the heating rate in the second stage is 2~4℃ / min, the heating rate in the third stage is 4~8℃ / min, and the holding time in the fourth stage is 25~50min.

9. The ultra-high silica, low aluminum, iron tailings-based high-strength lightweight ceramsite prepared by the preparation method according to any one of claims 1 to 8, characterized in that, The ultra-high silicon, low aluminum, and iron tailings-based high-strength lightweight ceramsite has a 1-hour water absorption rate of ≤10%, a cylinder compressive strength of ≥7MPa, and a bulk density of 800~1200kg / m³. 3 .